Composition for polarizing film, polarizing film, and display device including the polarizing film

Abstract

A composition for a polarizing film, including a polyolefin and a dichroic dye represented by Chemical Formula 1: wherein in Chemical Formula 1, groups and variables are the same as defined in the detailed description.

What is claimed is: 
     
       1. A composition for a polarizing film, comprising
 a polyolefin and 
 a dichroic dye represented by Chemical Formula 1: 
 
       
         
           
           
               
               
           
         
          wherein, in Chemical Formula 1,
 EWG is a halogen, C(═O)R, C(═O)OR′, a haloalkyl group, C(═O)Cl, CN, SO 3 R″, or NO 2 , wherein R, R′, and R″ are a C1 to C30 alkyl group, 
 Ar 1  is a C6 to C12 arylene group or a C4 to C12 heteroarylene group, 
 Ar 2  is a C12 to C20 arylene group or a C4 to C20 heteroarylene group, 
 R 1  and R 2  are independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted C1 to C20 alkylthio group, a substituted or unsubstituted C2 to C20 alkenyl group, or a substituted or unsubstituted C2 to C20 alkynyl group, provided that at least one of R 1  and R 2  is a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted C1 to C20 alkylthio group, a substituted or unsubstituted C2 to C20 alkenyl group, or a substituted or unsubstituted C2 to C20 alkynyl group, 
 R 3  and R 4  are independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, or a substituted or unsubstituted C1 to C20 alkylthio group, 
 
         m and n are integers of 1 or 2,
 R 1a  is hydrogen or a substituted or unsubstituted C1 to C30 alkyl group, 
 provided that R 1 , R 1a , and R 2  are not simultaneously hydrogen, 
 provided that a+p, q, and r do not exceed bonding valence of the phenylene group, Ar 1  and Ar 2 , respectively, and 
 R 5  and R 6  are independently hydrogen, a substituted or unsubstituted C1 to C10 alkyl group, wherein R 5  and R 6  are optionally linked to each other to provide a ring. 
 
       
     
     
       2. The composition for a polarizing film of  claim 1 , wherein the R 1  and R 2  are a substituted or unsubstituted C5 to C30 alkyl group, a substituted or unsubstituted C5 to C20 alkoxy group, a substituted or unsubstituted C5 to C20 alkylthio group, a substituted or unsubstituted C5 to C20 alkenyl group, or a substituted or unsubstituted C5 to C20 alkynyl group. 
     
     
       3. The composition for a polarizing film of  claim 1 , wherein Ar 1  is a phenylene group or a naphthylene group. 
     
     
       4. The composition for a polarizing film of  claim 1 , wherein the Ar 2  is a naphthylene group or an anthracenylene group. 
     
     
       5. The composition for a polarizing film of  claim 1 , wherein the dichroic dye is represented by Chemical Formula 2: 
       
         
           
           
               
               
           
         
         wherein, in Chemical Formula 2, 
         EWG is a halogen, C(═O)R, C(═O)OR′, a haloalkyl group, C(═O)Cl, CN, SO 3 R″, or NO 2 , wherein R, R′, and R″ are a C1 to C30 alkyl group, 
         R 1  and R 2  are independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted C1 to C20 alkylthio group, a substituted or unsubstituted C2 to C20 alkenyl group, or a substituted or unsubstituted C2 to C20 alkynyl group, provided that at least one of R 1  and R 2  is a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted C1 to C20 alkylthio group, a substituted or unsubstituted C2 to C20 alkenyl group, or a substituted or unsubstituted C2 to C20 alkynyl group, 
         R 3  and R 4  are independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, or a substituted or unsubstituted C1 to C20 alkylthio group, 
         m and n are integers of 1 or 2, 
         R 1a  to R 1c  are independently hydrogen, or a substituted or unsubstituted C1 to C30 alkyl group, 
         provided that R 1 , R 1a , R 2 , and R 1b  are not simultaneously hydrogen, p, q, r, a, b, and c are each an integer of 0 to 2, 
         provided that a+p, q+b do not exceed bonding valence of the corresponding phenylene group, and r+c does not exceed bonding valence of the naphthylene group, and 
         R 5  and R 6  are independently hydrogen, a substituted or unsubstituted C1 to C10 alkyl group, wherein R 5  and R 6  are optionally linked to each other to provide a ring. 
       
     
     
       6. The composition for a polarizing film of  claim 5 , wherein the R 1  and R 2  are independently a substituted or unsubstituted C5 to C30 alkyl group, a substituted or unsubstituted C5 to C20 alkoxy group, a substituted or unsubstituted C5 to C20 alkylthio group, a substituted or unsubstituted C5 to C20 alkenyl group, or a substituted or unsubstituted C5 to C20 alkynyl group. 
     
     
       7. The composition for a polarizing film of  claim 1 , wherein the dichroic dye has a decomposition temperature of greater than or equal to about 245° C. 
     
     
       8. The composition for a polarizing film of  claim 1 , wherein the polyolefin has a melting point of less than or equal to about 300° C. 
     
     
       9. The composition for a polarizing film of  claim 1 , wherein the polyolefin comprises polyethylene, polypropylene, a copolymer thereof, or a combination thereof. 
     
     
       10. The composition for a polarizing film of  claim 1 , wherein the polyolefin has a melt flow index of about 1 gram per 10 minutes to about 15 grams per 10 minutes. 
     
     
       11. The composition for a polarizing film of  claim 1 , wherein the polypropylene has a melt flow index of about 0.1 grams per 10 minutes to 5 grams per 10 minutes, and
 the polyethylene-polypropylene copolymer has a melt flow index of about 5 grams per 10 minutes to about 15 grams per 10 minutes. 
 
     
     
       12. The composition for a polarizing film of  claim 1 , wherein the polyolefin is a mixture of polypropylene and a polyethylene-polypropylene copolymer, and the polyethylene-polypropylene copolymer comprises about 1 to about 50 percent by weight of the polyethylene. 
     
     
       13. The composition for a polarizing film of  claim 1 , wherein the polyolefin comprises polypropylene and a polyethylene-polypropylene copolymer in a weight ratio of about 1:9 to about 9:1. 
     
     
       14. The composition for a polarizing film of  claim 1 , wherein an amount of the dichroic dye is about 0.01 to about 5 parts by weight based on 100 parts by weight of the polyolefin. 
     
     
       15. The composition for a polarizing film of  claim 14 , wherein an amount of the dichroic dye is about 0.05 to 1 part by weight based on 100 parts by weight of the polyolefin. 
     
     
       16. The composition for a polarizing film of  claim 1 , which has a solid content of greater than or equal to about 90 percent by weight. 
     
     
       17. The composition for a polarizing film of  claim 1 , which does not comprise a solvent. 
     
     
       18. A polarizing film comprising a molten mixture of the composition for a polarizing film of  claim 1 . 
     
     
       19. The polarizing film of  claim 18 , which has a dichroic ratio of about 3 to about 10 in a wavelength region of greater than or equal to about 600 nanometers. 
     
     
       20. The polarizing film of  claim 18 , wherein the dichroic dye is dispersed in the polyolefin, and
 the polyolefin is elongated in a uniaxial direction at an elongation rate of about 400 to about 1,000%. 
 
     
     
       21. A display device comprising the polarizing film of  claim 18 .